This backpack saved my life a few weeks ago when I was in a 2700' avalanche in the backcountry off Stevens Pass. There were three others caught in the avalanche who did not survive. I was the only one wearing this backpack and was the only survivor. My ABS pack saved my life and I hope they will continue to help save lives in the future. For me, the ABS brand pack is the standard for avalanche airbags and here is why I think so.
To begin, the dual airbag system ensures that if one inflation fails or one bag is damaged by trees, etc. you will still have at least one airbag fully inflated. Additionally, ABS is using new technology with their bag materials which creates a much lighter and much stronger bag. The airbag material is the same material used on zodiac boats which means that it is nearly impossible to shred if punctured. The trigger mechanism is a nearly fail safe pneumatic system that only takes approximately 18 pounds of force over 2 cm's to trigger inflation. Non-pnuematic systems can take up to 45 pounds of pressure over 6 inches in length trigger inflation. From my experience, once you're caught in an avalanche things happens so fast that the easier a trigger is to pull the better.
I also love the fact that the ABS is constructed of a base system that has the airbag safety system in it, and the actual backpack is zipped on allowing for different size packs to be attached. This, I believe, makes buying this pack a worthy investment because you are able to have different sized packs for different types of days. 90% of the time I use the Powder 15L, which fits my shovel, probe, some food, water, an extra pair of gloves, a thin layer, a few other small things, and my skins (at that point it's starting to get pretty tight). If I need more gear than this I would use the Vario 25L (or 40L). Please note that the Powder Line and the Vario Line are not interchangeable. I prefer the Powder Line because it is a little less bulky that the Vario system, but it is more limiting with only having the 5L and 15L as the two sizes.
These ABS backpacks are very durable (and I'm talking about the base system). My backpack went through some heavy forces in the avalanche so ABS did an integrity check on my pack. The pack was found to be completely intact and in perfect working condition, so I am still using the same base system.
The pack includes straps and an exterior helmet holder, so you can dangle stuff off if need be. The ski carry system is just okay (using the straps that are included), but it works and the pack is so awesome it is not the biggest deal to me. The waist buckle is strong and easy to use, I don't have to take my mittens off to lock and unlock the steel buckle.
ABS uses a nitrogen cartridge which makes it lighter and smaller than other brands. While some may scoff at the additional weight of an avy bag, the ABS pack does not feel heavy, it fits very snug on the body and I have never felt that my pack has extra weight to it when it's on my back.
Any kind of avalanche safety backpack is not the end all be all device that usurps the necessary knowledge to be in the backcountry, your sound judgement, and the other mandatory backcountry tools such as a transceiver, shovel, and probe. Rather, these backpacks are a last ditch effort if you find yourself in an unfortunate situation of being caught in an avalanche. Accidents can happen and these packs can help save your life. It saved mine.